The Progression of Power
A Look at Battery Technology Today and Tomorrow

Thanks to ongoing advancements, battery-operated equipment is turning up more and more in professional landscapers' inventories. Electric motors can perform at the same level as combustion engines, so a battery-powered leaf blower can output just about as much cubic feet per minute as a gas model: over 500 CFM for handheld units and close to 600 for backpack ones. One of the main hurdles of adoption though is the limited energy a battery provides. David Glueck, senior product manager at electric equipment manufacturer Greenworks, says better battery management is one solution. To that end, his company is developing four-port and six-port chargers that replenish batteries sequentially overnight to meet a maintenance pro's daily needs, which Glueck and colleagues have found to average 20 to 30 batteries.

With all the strides forward made recently in battery technology, especially in the automotive industry, it is not a stretch to see the dominance of this power source in the near future for outdoor power equipment (OPE) applications. With that in mind, LC/DBM explored the current state and coming expectations of this subject.

About a year ago, two LC/DBM editors tested a leaf blower at a regional trade show and were pleasantly surprised at the results. One of them, a small-framed female, said, "I could lift it with one hand and operate it and it didn't push me back. And it was pretty powerful."

Her companion that day added, "When she first turned it on, the force of it threw (the blower's nozzle) back about 90 degrees. It was full power right off the bat."

Before discussing where the industry is presently at, David Glueck, senior product manager at electric equipment manufacturer Greenworks, broke down the essential aspects of batteries. He explained that voltage is the horsepower or torque a battery can produce and that ampere-hours (Ah) is its capacity, or how much energy it can store. Drawing that energy out - a piece of equipment's startup speed - is referred to as discharge (being able to discharge quickly is critical for efficient operation of outdoor power products: think of using a chainsaw to limb a tree).

The voltage of a battery relates to the torque or "horsepower" of it and the ampere hours (Ah) is how much energy it can store, similar to how much gas a piece of equipment's fuel tank holds. This all figures in to the runtime of that equipment before a "refueling" is needed. That is one area that technological improvements are trying to improve upon. Another is increasing the number of cycles (discharge/recharge) a battery can go through before their power starts to degrade. Presently it is about 500 cycles.

The manufacturer of this battery-powered hedgecutter publicizes its noise level at 96 decibels, or half as loud (approx. 99 decibels) as similar combustion engine devices (since a decibel is a logarithmic unit, by just lowering noise output three decibels, the volume of a piece of equipment is decreased by 50 percent).

The typical cell of a battery used to power OPE puts out about four volts so a 20 volt variety would have five cells. Increasing volts is increasing cells and of course increasing the size of the battery, which has understandable limits when it comes to certain types of equipment, such as those used for landscape maintenance.

According to Glueck, the standard Ah of a cell has been two for a while. Cells in a given battery can be used in unison but they can also be used in series, which then essentially increases the capacity of that battery. For example, using only 10 cells at a time of an 80-volt model rated at 2 Ah would cut the volts to 40 but increase the Ah to four.

"What we are seeing in the market right now are higher amp-hour cells coming out," says Glueck. "Now you are seeing two and a half and three amp-hour ones and soon they should have four amp-hour cells coming into the market."

Brushless motors, which have been in use for about a decade, have proven to be efficient and reliable because there are not many moving parts and not many parts that touch. This also increases the life expectancy in these motors.

As far as the landscape maintenance tools themselves go, and whether battery-powered versions of all of them have found acceptance by professionals, Glueck singled out leaf blowers as having the hardest time doing so because of runtime issues.

"With a two and a half amp hour battery, you get about 15 to 18 minutes at highest speed," he asserts. "And everyone wants to use the highest speed."

This problem was echoed by professional landscapers at a recent city council meeting in Palm Springs where residents voiced their opinions about a proposed gas-powered leaf blower ban. Local broadcaster KESQ-TV reported that some complained about the efficiency of battery-powered blowers.

"It is just not going to be effective for us," said Raul Salgado, owner of Salgado Landscaping. "Battery-operated stuff for us gets one hour or two hours. It's just not enough time,"

According to Glueck, the cells in most batteries in the industry each deliver about four volts standard so a 40-volt battery would have 10 cells. Individual cells can have higher voltage but that changes the makeup of the battery and the size.

Glueck said the most efficient handheld, battery-powered tools are chainsaws and hedge trimmers, and his company's ZTR gets about six hours of runtime on their new 13.8 kilowatt battery, or as he puts it, "enough to get you through your day."

On another topic, Glueck was asked if he is coming across companies that use battery-powered equipment as much as a marketing tool as anything else.

"We have seen landscapers where that is the pillar of their business model - where they acquire customers on the fact that they are less noisy while they are working and cleaner for the environment."

As an example of this, Mean Green Mowers recently reported that the electric maintenance division of International Landscaping, based in Ontario, Canada, launched in 2016 and has already grown to about 500 acres serviced each week. Michael Anthony Gucciardi, the company's account manager, is confident about future demand for this special service.

"We're getting to the point now where we have the technology and the equipment that we need, as landscape professionals, to do the work in an efficient and effective way without producing harmful carbon emissions," he says. "We are hearing from our clients, particularly from large property management firms, that it is important to them and their tenants to be environmentally friendly and to do their part to ensure a healthy future for our communities."

Looking further down the line, Glueck offered sodium ion technology as having, "very high hopes for the industry."
He explained that since lithium is a rare earth element, and a finite mineral, it impacts the cost-effectiveness of battery-operated OPE on a professional level. But with sodium in such abundance, lower battery costs lessens that impact.

Glueck asserts that these materials hold on to energy very well, which should increase the capacities of batteries made from them. But currently, the tradeoff is that charge times are longer than, and discharge is not as quick as, lithium ion batteries.

"Science is working on those two hurdles, which are vast, but I see that as the next evolution of bringing battery costs down," he predicts.

The process of charging batteries is another area of focus for improvement. Glueck points to EV charging stations, 4000 locations and growing, as an infrastructure that offers potential for this - for instance replenishing batteries at a station during a lunch break.
And increasing the speed to complete a charge will also be a big help. He expects that advancement to likewise come from the automotive industry and then be adopted by OPE manufacturers. At present, Tesla's rapid charger boasts a 45-minute charge cycle and there are companies claiming theirs can do it in 15 minutes.

Something that Glueck has "been trying to push, is a way to charge on-the-go and limit the amount of batteries on
the truck."

However, a cost analysis he did on using deep-cycle, lead-acid batteries to charge equipment batteries in the field showed that it was almost as expensive as just buying more equipment batteries, which then leads back to the issue of better battery management and ease of use.

Motors are getting smaller, as are the electronic circuit boards that control them, which will facilitate increasing performances out of smaller packages.

Finally, when asked for a prediction of how long it might be before battery-powered equipment will be the rule instead of the exception in the landscape industry, Glueck referenced a German law that mandates that combustion engines will no longer be available for sale in that country starting in 2030.

In the end though, it might be the people that landscapers work for that affect a complete transition. John Chiarella, who as owner of Ultimate Services, a professional grounds management company, has logged about 50 years in the industry (see page 26), admits that though battery-powered equipment isn't quite on par with gas-powered models yet, "Sooner or later customers are not going to want any noise or any pollutants and that probably will be the only way to go."

This Solar Assisted Mower (S.A.M.) option not only shades the operator, but energy collected from its solar cells is immediately converted to power for use by the pure electric machine.

In bare tool costs, electric models are about the same or less than gas units. And their energy sources are predicted to decrease in price thanks to the development of sodium ion batteries, which, when compared to lithium ion batteries, are cheaper to make but reported to have, at present, shortcomings that limit their effectiveness to uses where weight and energy density aren't as important.

The process of charging batteries is another area of focus for improvement. Glueck points to EV charging stations, 4000 locations and growing, as an infrastructure that offers potential for this - for instance replenishing batteries at a station during a lunch break.
And increasing the speed to complete a charge will also be a big help. He expects that advancement to likewise come from the automotive industry and then be adopted by OPE manufacturers. At present, Tesla's rapid charger boasts a 45-minute charge cycle and there are companies claiming theirs can do it in 15 minutes.

Something that Glueck has "been trying to push, is a way to charge on-the-go and limit the amount of batteries on
the truck."

However, a cost analysis he did on using deep-cycle, lead-acid batteries to charge equipment batteries in the field showed that it was almost as expensive as just buying more equipment batteries, which then leads back to the issue of better battery management and ease of use.

Motors are getting smaller, as are the electronic circuit boards that control them, which will facilitate increasing performances out of smaller packages.

Finally, when asked for a prediction of how long it might be before battery-powered equipment will be the rule instead of the exception in the landscape industry, Glueck referenced a German law that mandates that combustion engines will no longer be available for sale in that country starting in 2030.

In the end though, it might be the people that landscapers work for that affect a complete transition. John Chiarella, who as owner of Ultimate Services, a professional grounds management company, has logged about 50 years in the industry (see page 26), admits that though battery-powered equipment isn't quite on par with gas-powered models yet, "Sooner or later customers are not going to want any noise or any pollutants and that probably will be the only way to go."